Question

我想用Microsoft Visual Studio 2015编译的C / C ++代码创建服务。我编译了我的代码，并从app可执行文件中创建了一个sc.exe的服务。我的代码包含一个无限循环，它在一段时间内将一个简单的字符串写入一个静态文件。创建服务并重新启动后，似乎服务自动停止。直接运行时，可执行文件正常工作。

以下是代码：

#include "stdafx.h"
#include <string>
#include <cstdio>
#include <windows.h>


using namespace std;

void write_txt_file(string file_name, string input) {
    /*
    write a string to a specific txt file
    */
    FILE *f = fopen(file_name.c_str(), "a+");
    fprintf(f, "%s\n", input.c_str());
    fclose(f);
}

int main(int argc, char** argv)
{
    int i = 0;
    while (true) {
        write_txt_file("C:\\...\\Desktop\\out.txt", "Writing...#" + to_string(i));
        Sleep(5000);
        i++;
    }
}

以下是我用来创建服务的命令：

sc.exe create My_service binPath= "<path to executable>" start= auto

并且out.txt文件的输出为：

Writing...#0
Writing...#1
Writing...#2
Writing...#3
Writing...#4
Writing...#5
Writing...#6
Writing...#7
Writing...#8

Answer 1

在@Aconcagua和this reference的帮助下，我找到了一个简单的代码，让我的代码与windows服务兼容。在函数ServiceWorkerThread中，您需要将循环放在while块中。该服务可以安全停止。

#include <Windows.h>
#include <tchar.h>
#include <string>
#include <cstdio>


SERVICE_STATUS        g_ServiceStatus = {0};
SERVICE_STATUS_HANDLE g_StatusHandle = NULL;
HANDLE                g_ServiceStopEvent = INVALID_HANDLE_VALUE;

VOID WINAPI ServiceMain (DWORD argc, LPTSTR *argv);
VOID WINAPI ServiceCtrlHandler (DWORD);
DWORD WINAPI ServiceWorkerThread (LPVOID lpParam);

#define SERVICE_NAME  _T("My Sample Service")


using namespace std;

void write_txt_file(string file_name, string input) {
    /*
    write a string to a specific txt file
    */
    FILE *f = fopen(file_name.c_str(), "a+");
    fprintf(f, "%s\n", input.c_str());
    fclose(f);
}


int _tmain (int argc, TCHAR *argv[])
{
    OutputDebugString(_T("My Sample Service: Main: Entry"));

    SERVICE_TABLE_ENTRY ServiceTable[] = 
    {
        {SERVICE_NAME, (LPSERVICE_MAIN_FUNCTION) ServiceMain},
        {NULL, NULL}
    };

    if (StartServiceCtrlDispatcher (ServiceTable) == FALSE)
    {
       OutputDebugString(_T("My Sample Service: Main: StartServiceCtrlDispatcher returned error"));
       return GetLastError ();
    }

    OutputDebugString(_T("My Sample Service: Main: Exit"));
    return 0;
}


VOID WINAPI ServiceMain (DWORD argc, LPTSTR *argv)
{
    DWORD Status = E_FAIL;

    OutputDebugString(_T("My Sample Service: ServiceMain: Entry"));

    g_StatusHandle = RegisterServiceCtrlHandler (SERVICE_NAME, ServiceCtrlHandler);

    if (g_StatusHandle == NULL) 
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: RegisterServiceCtrlHandler returned error"));
        goto EXIT;
    }

    // Tell the service controller we are starting
    ZeroMemory (&g_ServiceStatus, sizeof (g_ServiceStatus));
    g_ServiceStatus.dwServiceType = SERVICE_WIN32_OWN_PROCESS;
    g_ServiceStatus.dwControlsAccepted = 0;
    g_ServiceStatus.dwCurrentState = SERVICE_START_PENDING;
    g_ServiceStatus.dwWin32ExitCode = 0;
    g_ServiceStatus.dwServiceSpecificExitCode = 0;
    g_ServiceStatus.dwCheckPoint = 0;

    if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE) 
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
    }

    /* 
     * Perform tasks neccesary to start the service here
     */
    OutputDebugString(_T("My Sample Service: ServiceMain: Performing Service Start Operations"));

    // Create stop event to wait on later.
    g_ServiceStopEvent = CreateEvent (NULL, TRUE, FALSE, NULL);
    if (g_ServiceStopEvent == NULL) 
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: CreateEvent(g_ServiceStopEvent) returned error"));

        g_ServiceStatus.dwControlsAccepted = 0;
        g_ServiceStatus.dwCurrentState = SERVICE_STOPPED;
        g_ServiceStatus.dwWin32ExitCode = GetLastError();
        g_ServiceStatus.dwCheckPoint = 1;

        if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
        {
            OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
        }
        goto EXIT; 
    }    

    // Tell the service controller we are started
    g_ServiceStatus.dwControlsAccepted = SERVICE_ACCEPT_STOP;
    g_ServiceStatus.dwCurrentState = SERVICE_RUNNING;
    g_ServiceStatus.dwWin32ExitCode = 0;
    g_ServiceStatus.dwCheckPoint = 0;

    if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
    }

    // Start the thread that will perform the main task of the service
    HANDLE hThread = CreateThread (NULL, 0, ServiceWorkerThread, NULL, 0, NULL);

    OutputDebugString(_T("My Sample Service: ServiceMain: Waiting for Worker Thread to complete"));

    // Wait until our worker thread exits effectively signaling that the service needs to stop
    WaitForSingleObject (hThread, INFINITE);

    OutputDebugString(_T("My Sample Service: ServiceMain: Worker Thread Stop Event signaled"));


    /* 
     * Perform any cleanup tasks
     */
    OutputDebugString(_T("My Sample Service: ServiceMain: Performing Cleanup Operations"));

    CloseHandle (g_ServiceStopEvent);

    g_ServiceStatus.dwControlsAccepted = 0;
    g_ServiceStatus.dwCurrentState = SERVICE_STOPPED;
    g_ServiceStatus.dwWin32ExitCode = 0;
    g_ServiceStatus.dwCheckPoint = 3;

    if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
    {
        OutputDebugString(_T("My Sample Service: ServiceMain: SetServiceStatus returned error"));
    }

    EXIT:
    OutputDebugString(_T("My Sample Service: ServiceMain: Exit"));

    return;
}


VOID WINAPI ServiceCtrlHandler (DWORD CtrlCode)
{
    OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: Entry"));

    switch (CtrlCode) 
    {
     case SERVICE_CONTROL_STOP :

        OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: SERVICE_CONTROL_STOP Request"));

        if (g_ServiceStatus.dwCurrentState != SERVICE_RUNNING)
           break;

        /* 
         * Perform tasks neccesary to stop the service here 
         */

        g_ServiceStatus.dwControlsAccepted = 0;
        g_ServiceStatus.dwCurrentState = SERVICE_STOP_PENDING;
        g_ServiceStatus.dwWin32ExitCode = 0;
        g_ServiceStatus.dwCheckPoint = 4;

        if (SetServiceStatus (g_StatusHandle, &g_ServiceStatus) == FALSE)
        {
            OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: SetServiceStatus returned error"));
        }

        // This will signal the worker thread to start shutting down
        SetEvent (g_ServiceStopEvent);

        break;

     default:
         break;
    }

    OutputDebugString(_T("My Sample Service: ServiceCtrlHandler: Exit"));
}


DWORD WINAPI ServiceWorkerThread (LPVOID lpParam)
{
    OutputDebugString(_T("My Sample Service: ServiceWorkerThread: Entry"));
    int i = 0;
    //  Periodically check if the service has been requested to stop
    while (WaitForSingleObject(g_ServiceStopEvent, 0) != WAIT_OBJECT_0)
    {        
        /* 
         * Perform main service function here
         */

        //while (true) {
            write_txt_file("C:\\...\\out.txt", "Writing...#" + to_string(i));
            Sleep(5000);
            i++;
    //  }
        //  Simulate some work by sleeping
        Sleep(3000);
    }

    OutputDebugString(_T("My Sample Service: ServiceWorkerThread: Exit"));

    return ERROR_SUCCESS;
}

Answer 2

Windows服务不仅仅是简单的可执行文件，例如您编写的一个，而是需要遵循特定模式如何与操作系统进行通信。您可以在microsoft网站上找到所有必要的信息，此外，任何优秀的搜索引擎都会显示无数的编写示例（例如here）。

或者，您可以使用Windows服务包装器（您可以尝试this one - 但需要说，我没有评估它 - 或者搜索另一个合适的包装器。）

旁注：为什么你的可执行文件会停止执行？好吧，因为它没有遵循上面提到的模式，我。即没有及时通知操作系统其状态（见链接）因此被操作系统再次关闭（杀死），因为它认为你的“服务”无法运行......

从已编译的应用

2 个答案: